my guess is a polished aluminium disc
Self adhesive foil film is more likely. I bet a window tinting/vehicle sign writing shop could do that on a flat disc. No way you could do it on a lenticular disc, which would look really cool.
@gbj_tester started
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Self adhesive foil film is more likely. I bet a window tinting/vehicle sign writing shop could do that on a flat disc. No way you could do it on a lenticular disc, which would look really cool.